Bonding is a commonly used technique in the semiconductor process. Whether the bonding interface is in well contact is an important indicator for measuring bonding quality. In the prior art, after two substrates are bonded, a region where bonding contact is poor may sometimes be found on an opposite side of the opening of the substrate. FIG. 1 is a schematic diagram of a defective region generated on a bonding interface in the prior art. As illustrated in FIG. 1, poor contact in the bonding interface may be found in the bonding region opposite to an opening 11 of a substrate 10. How to avoid poor contact in this region is a problem to be urgently solved in the prior art.